The metadata below describe the original scanning. Follow the "All Files: HTTP" link in the "View the book" box to the left to find XML files that contain more metadata about the original images and the derived formats (OCR results, PDF etc.). See also the What is the directory structure for the texts? FAQ for information about file content and naming conventions.
"Commenced by the author in 1902, as a doctoral dissertation in Columbia University and in 1906, for that purpose, the first six chapters were privately printed, but in a somewhat different form from that in which they now appear."--Pref